One plant that has not suffered from all of these changes is Angelonia, Serena Purple. It has tolerated dry conditions, wet conditions, and now additional sun. I bought 2 of these plants in spring. This one is planted in the east bed that runs along the fence. It is under a wax myrtle. It gets good sun, but is somewhat protected from the hot west sun.
"The Angelonia 'Purple' provides masses of 3/4-inch blooms that open along plentiful long, elegant stems all summer long. A fine plant for hot, dry, humid, and even wet garden spots. This super-easy sun-lover is grown like Salvia and just as beautiful! 10 to 12 inches high, 12 to 14 inches wide."
And to top it off--you do not need to deadhead!
Fresh flowering stems simply arise to replace the old ones! Not only is it heat tolerant, it is humidity tolerant as well. The Serena series of Angelonia comes in this purple color, plus pink and white. I cannot recommend this Angelonia enough. If we can grow it this well in our conditions, it is a keeper!